5 replies to this topic

[Meersy]

Hi all, hope you can help.
Having a bit of a problem getting the mini running again.
It was working fine but I've recently serviced it with New plugs, leads, dizzy cap and coil. Its running electronic ignition and it will start and run.
However when it started it was running very rough (I believe it was hunting) so i played with the mixture screw and the revs shot up to about 3000.
Now though when it starts on the choke it idles about 1200 then within 30 secs is back up to 3000.
When the choke is off the car stalls very quickly.
Im at a loss adjusting the idle seemed to have no effect. I thought I may have leaned it off too much but richening the fuel seemed to do nothing.
Its a Hif44 carb by the way.
Any ideas?

[sledgehammer]

check for air leaks , or cracked pipes << this would give high idle , if not ...

any chance you moved the dizzi when putting the cap on ?

have you just put the electronic ign on ?

is it the correct coil - ballast or not ?

I'm assuming 1275 /13-- with the hif44 carb ?

set timing , check for leaks , then play with mixture

best of luck

[jaydee]

Air leak or no oil in the dashpot.
As above, refille the dashop oil, check timing, check for air leaks, then adjust mixture and idle speed.

[tiger99]

I doubt that it is anything to do with the dashpot oil level, as that mostly affects acceleration, not idling, but it ought to be checked anyway.

As always, the last thing that was done before it went wrong is the prime suspect. I strongly suspect that the mixture adjuster is a very long way off. You should first check the fuel level in the float chamber, and if necessary replace the float and needle valve, then follow the adjustment procedure in the Haynes manual, which is a bit long to reproduce here. You will need a tachometer and an exhaust gas analyser, so unless you have these, it may be cheaper to have a garage or mobile engine tuner look at it.

It is also possible that the temperature compensation mechanism has failed, which could seriously affect the mixture. This relies on a bimetallic lever which moves the jet up and down, so the lever has to be intact and the jet free to move against its spring, so you should probably strip these bits out, check and clean, before going further.

[Meersy]

OK its been a while but I've finally got it running ok, thanks for all the suggestions.
There was an air leak. My dizzy has no vac so the little tube on the carb was open.
This is now blocked and ive got the car up to temp today and managed to get the idle down to about 1200 running no choke.
Now my problem is the exhaust seems to "pop" alot and idle isnt stable.
The engine is a 1330 with a 286 cam but it seems to be misfiring maybe?
Ive tried the old coil and re gapped the plugs (had them at 30 thou now at 25 just incase)
Also ive used a colourtune to check the fueling and that seems spot on now (or as good as i can get it)
I did reset the timing after the electronic ignition went in but I borrowed a timing light which i dont have now.
Would retarded timing cause this?
Thanks again

[jaydee]

A 1330 with a 286 will have a broken idle, raise the speed at about 1200 rpm and it will smooth out a little.